Postoperative Plasma Mitochondrial DNA and Cytokine Profiles of Elderly Patients Undergoing Minimally Invasive Aortic Valve Replacement.

INTRODUCTION: Mitochondrial DNA (mtDNA) is gaining increasing interest as a marker of cellular damage and could also act as an inflammatory mediator in cardiopulmonary bypass induced postoperative inflammatory response. Although minimally invasive heart valve surgery reportedly reduces inflammation, the mtDNA and cytokine profile in this context remains unclear. MATERIALS AND METHODS: Here, we report a prospective series of 40 elderly patients with aortic stenosis who underwent bioprosthetic aortic valve replacement (AVR) through upper ministernotomy with either a sutureless (n = 20) or a conventional (n = 20) valve. Primary end points included serial plasma levels of mtDNA (T1: at baseline; T2: 4 hours after surgery; and T3: 24s hour after surgery), cytokines (interleukin-6 [IL-6], tumor necrosis factor-α [TNF-α]), and myocardial necrosis biomarkers (MNBs), whereas secondary end points included clinical and echocardiographic data. RESULTS: Significant increases in the postoperative plasma levels (T2) of mtDNA, cytokines, and MNBs were observed in all patients. The postoperative plasma levels of mtDNA, TNF-α, and MNBs showed no significant differences between the treatment groups, although there was a trend toward lower levels in the sutureless group. The decreases in aortic cross-clamp and cardiopulmonary bypass times seen in the sutureless group were associated with significant lower postoperative levels (T2 and T3) of IL-6. CONCLUSION: AVR through upper ministernotomy was associated with a significant increase in postoperative plasma levels of mtDNA and cytokines. There was no difference in the mtDNA levels between the sutureless and conventional valve groups, suggesting a similar level of inflammation in both groups. However, the shorter operation time observed in the sutureless valve group was associated with significantly lower postoperative levels of IL-6, indicating potential clinical benefits.

Comparison of the effectiveness of circumferential versus non-circumferential spread in median and ulnar nerve blocks. A double-blind randomized clinical trial.

BACKGROUND AND OBJECTIVES: Circumferential (C) spread of local anesthetic around the nerve is recommended for a successful nerve block. We tested the hypothesis that C spread produces a more complete block than non-circumferential (NC) spread. METHODS: We randomized 124 patients undergoing open carpal tunnel syndrome surgery to receive C or NC spread ultrasound-guided median and ulnar nerve blocks. The primary outcome was the proportion of patients who developed complete sensory block measured at 5, 15 and 30 min. The loss of cold sensation was graded as: 0 (complete block), 1 (incomplete block), or 2 (no block). Secondary outcomes included motor block, nerve swelling and adverse events. RESULTS: In group C, complete sensory block at 5 min was 2.4 (95% CI 1.0 to 5.7; p=0.04) times more frequent in the median nerve and 3.0 (95% CI 1.2 to 7.2; p=0.01) times more frequent in the ulnar nerve compared with group C. However, at 15 and 30 min, it was similar between groups. Complete motor block was more frequent in group C than in group NC for both the median nerve: 1.5 (95% CI 1.1 to 2.2; p<0.01) at 15 min, 1.1 (95% CI 1.0 to 1.2; p=0.02) at 30 min, and the ulnar nerve: 1.7 (95% CI 1.2 to 2.6; p<0.01) at 15 min, 1.2 (95% CI 1.0 to 1.4; p<0.01) at 30 min. The incidence of nerve swelling and adverse effects was similar between groups. CONCLUSIONS: C spread around the median and ulnar nerves at the level of the antecubital fossa generates more complete sensory and motor blocks compared with NC spread. TRIAL REGISTRATION NUMBER: EudraCT 2011-002608-34 and NCT01603680.